Thomas Frank Flemmig

Implants in the Medically Compromised Patient

Dental clinicians are confronted with an increasing number of medically compromised patients who require implant surgery for their oral rehabilitation. However, there are few guidelines on dental implant therapy in this patient category, so that numerous issues regarding pre- and post-operative management remain unclear to the dental clinician. Therefore, the aim of the present review is to offer a critical evaluation of the literature and to provide the clinician with scientifically based data for implant therapy in the medically compromised patient. This review presents the current knowledge regarding the influence of the most common systemic and local diseases on the outcome of dental implant therapy, e.g., abnormalities in bone metabolism, diabetes mellitus, xerostomia, and ectodermal dysplasias. Specific pathophysiologic aspects of the above-mentioned diseases as well as their potential implications for implant success are critically appraised. In line with these implications, guidelines for pre- and post-operative management that may assist in the successful implant-supported rehabilitation of this patient category are proposed.

Caspase activation is involved in chronic periodontitis

Periodontitis, a common infectious disease, is initiated by various gram‐negative bacteria and characterized by the destruction of the periodontal tissue. Here, we investigated the role of caspases, intracellular proteases that are the key mediators of apoptosis. We show that activation of caspase‐3 and caspase‐7 is considerably enhanced in gingival tissue from patients with periodontitis. We also demonstrate in in vitro experiments that various periodontopathic bacteria exert a direct growth‐suppressing effect and, moreover, can trigger a host‐mediated cytotoxic activity involving the CD95 death receptor. Our data suggest that caspase activation is a prominent feature in periodontitis‐associated tissue injury.

Multifactorial assessment of predictors for prevention of periodontal disease progression

Univariate approaches have identified single factors influencing periodontal disease progression. The aim of this explorative approach was to assess the influence of various predictive factors responsible for the prevention of periodontal disease progression in the same patient sample. Patients with untreated chronic periodontitis underwent subgingival debridement alone or in combination with adjunctive antimicrobial therapy (systemic amoxicillin and metronidazole/7xa0days plus supragingival CHX irrigation). Supportive periodontal therapy was performed over a 24-month period. As predictors, clinical, microbial, immunological, and genetic parameters were assessed. The primary outcome variable was the percentage of teeth without attachment loss ≥2xa0mm over the study period (stability of attachment). At 24xa0months, multiple regression analysis identified adjunctive antimicrobial therapy for teeth with initially at least one site showing a pocket probing depth of ≥7xa0mm and IgG4 reactivity against a 110-kDa protein of A. actinomycetemcomitans at teeth with initial pocket probing depths ≤6xa0mm as main predictors of long-term attachment stability (p<0.05). Other parameters failed to influence treatment outcome. Adjunctive antimicrobial therapy and antibody reactivity may be dominant factors influencing the prevention of attachment loss in patients receiving periodontal therapy.

Assessment of root curvature and distance using computed tomography.

Abstract. The safety and efficacy of subgingival root surface instrumentation may be enhanced by optimized adaptation between instrument and treated surface. Thus, detailed knowledge of root geometry may allow advances in instrument design. The aim of this study was therefore to measure root radii of various tooth types as well as distances between tooth roots using computed tomography. Two hundred sixteen teeth in eight patients were studied, with cross sections of teeth at the level of the cemento-enamel junction (CEJ) being regarded as ellipses. The maximum radii of ellipses were calculated and averaged for each tooth surface within various tooth groups. In addition, the spacing between roots at CEJ level and 5xa0mm below the CEJ was measured. Mean radii varied from 1.09±0.50xa0mm (lower incisor, lingual) to 13.7±0.96xa0mm (upper molar, mesial). Radii of 1xa0mm to 6xa0mm were most frequently found at buccal, palatal, and lingual surfaces, whereas the majority of radii were between 2xa0mm and 11xa0mm at mesial and distal sites. Root distance varied between 1.04±0.49xa0mm (lower incisors, CEJ level) and 2.81±1.70xa0mm (lower molars, 5xa0mm below CEJ). The curvature of an instrument for root surface instrumentation should correspond to a radius of at least 11xa0mm to achieve maximum adaptation to the treated surface, and the width of the working end should be less than 1xa0mm to allow sufficient interdental instrumentation.